Respirator User's Notice - Use of Unapproved Subassemblies

HPPOS-147 PDR-9111220069

This notice states that NIOSH / MSHA approves only complete respirator assemblies and not subassemblies such as cylinders or air supply hoses. Users of approved respirators must not interchange subassemblies or make unapproved modifications to respiratory protection devices.

The National Institute for Occupational Safety and Health (NIOSH) had received many questions and complaints in regard to the interchangeability of respirator subassemblies and unapproved modifications to NIOSH / MSHA certified respirators. Further, some problems reported to NIOSH had, upon investigation, been found to have been caused by user's modifying certified respirators that resulted in the modified respirator failing to perform as anticipated, thus jeopardizing the respirator user.

NIOSH / MSHA respirator certification regulations, Title 30 Code of Federal Regulations Part 11 (30 CFR 11), state that approved respirators "are maintained in an approved condition and are the same in all respects as those respirators for which a certificate has been issued." [30 CFR 11, 11.2 (b)] In addition, the regulations permit NIOSH / MSHA to approve only complete respirator assemblies and prohibit the approval of respirator subassemblies such as cylinders or air supply hoses.

These requirements are intended to ensure that one manufacturer has overall control and responsibility for the integrity of the approved respirator. In some cases even minor modifications to respirators may make significant changes in the performance of the respirator.

Manufacturers who modify certified respirators must test the modification to determine if the respirator continues to meet the minimum requirements of 30 CFR 11, and must submit the modifications to NIOSH.

A user who modifies a certified respirator may not be able to determine whether a change will decrease respiratory protection. Several cases have been reported to NIOSH where unapproved modifications or use of an unapproved subassembly have resulted in respirator failures.

Therefore, users of NIOSH / MSHA approved respirators are cautioned against interchanging subassemblies or making unapproved modifications to their respiratory protective devices.